For connecting a coaxial cable used for transmission of high frequency signals, for example, in television broadcasting or data communication, a connector for a coaxial cable such as an F-type connector has been used in which a connector plug attached to the top end of the coaxial cable is inserted and fixed to a receptacle formed on the side of a high frequency equipment.
FIGS. 4(a)-(f) are explanatory views showing an existent connector plug for a coaxial cable used in usual domestic wirings.
In a coaxial cable 11, as shown in FIG. 4(a), a central conductor 12, an insulator 13, an outer conductor 14 comprising braided wires as a shield, and a sheath 15 protecting them are arranged concentrically from a center of the coaxial cable.
In a connector plug 21 as shown in FIG. 4(b), a connection nut 23 is rotationally attached to a tubular ferrule 22 inserted between the insulator 13 and the outer conductor 14 from the top end of the coaxial cable 11, and the sheath 15 is clamped over the ferrule 22 by a clamping ring 24 in a state of inserting the ferrule 22 between the insulator 13 and the outer conductor 14.
When the connector plug 21 is attached to the top end 11a of the coaxial cable 11, the clamping ring 24 is inserted in a state of exposing the central conductor 12 and the outer conductor 14 each by a predetermined length as shown in FIG. 4(a), then the tubular ferrule 22 is firmly inserted between the insulator 13 and the outer conductor 14 as shown in FIGS. 4(b) to (c), and the clamping ring 24 is deformed by using pincers, etc., in a state of locating the clamping ring 24 above the ferrule 22 as shown in FIG. 4(c), to complete the attachment as shown in FIGS. 4(d) to (f).
In a case of using the thus mounted connector plug 21, it may be inserted into a receptacle formed in a high frequency equipment and a connection nut 23 is screw coupled to a male screw formed at the outer periphery of the receptacle.
In the above-mentioned type of deforming and fixing of the clamping ring 24, if the ferrule 22 should happen to be inserted initially without insertion of the clamping ring 24, since the ferrule could not be detached simply, it was obliged to incise the sheath 15, detach the ferrule 22, and then cut the top end 11a of the coaxial cable 11, and conduct fabrication again.
Further, deforming the clamping ring 24 resulted in a tendency to cause attaching failure due to a lack of reliability, such that when an excessive force is applied to injure the clamping ring 24 this induces cracking therefrom and causes easy detachment and, on the other hand, when the force is insufficient, tightening becomes lose to cause easy detachment.
While a connector plug of high reliability for professional use employed, for example, in office wirings of broadcasting stations is present, this not only requires an expensive exclusive clamping tool but also is complicate and requires a number of parts, which increases the cost and can not be used as the domestic use.